This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Dennis Pantazatos was recruited to the Division of Hematology and Oncology by Drs. Hixson and Quesenberry (Division Director, PI on COBRE for Stem Cell Biology). Dennis is supported by both Divisional and COBRE funds. Dennis obtained a BS with honors in biomedical engineering from Northwestern University, an MS in human genetics from the University of Michigan and a PhD in biomedical sciences from UCSD. His PhD research involved the application of deuterium exchange mass spectrometry (DXMS) for protein 3-D conformational analysis and protein ligand interactions. He has an excellent publication record (PNAS, Molecular Pharmacology, J Biological Chemistry, Biochemistry, J of Membrane Biology) and is an inventor on a patent for the use of DXMS for protein structure determinations. Dennis will receive full project support to apply DXMS and image mass spectrometry (IMS) to map the differences in the conformational changes and contact points when an EGFR inhibitor binds to wild type EGFR or mutant forms that are resistant to inhibition. He will also develop methods for mapping ligand receptor interactions in vivo using DXMS in combination with IMS. We feel fortunate to have recruited Dennis and are excited by the potential for collaborative research using his expertise in mass spectrometry and protein structure.